The present invention relates to the field of communication systems. More specifically, the present invention relates to systems and methods that analyze the performance of a digital wireless network.
The wireless communication industry has made tremendous strides in commercial operations throughout the world. Growth in major metropolitan areas has far exceeded expectations and is rapidly outstripping network capacity, that is, the information carrying ability of the network. Digital communication technologies, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Global System for Mobile Communications (GSM), and so forth, are emerging as techniques for increasing the capacity of wireless networks to support call traffic. Such digital technologies result in substantial increases of capacity of the RF spectrum, for example, up to ten times that of an analog technology, such as the Advanced Mobile Phone Service (AMPS). In addition, digital technology has the potential to mitigate three major problems encountered by users of analog technology, i.e., static, loss/interruption of signal when passing between cells, and failure to get a connection because of congestion.
In order to design efficient digital wireless networks, designers need to be able to quickly and accurately evaluate the performance of a proposed wireless communication network, such as a CDMA wireless network. An accurate network analysis can be used to evaluate the network design and identify problematic sectors or cells. In addition, an accurate network analysis will allow the network designer to better estimate how well equipment settings will perform given the required, or expected, call traffic levels.
A CDMA wireless network provides the capability of two-way communication between a number of user mobile stations and corresponding servers, or base stations. Each direction of communication is performed on a separate radio link and involves a different set of system functions. The communication link from a server to a mobile station is referred to as the forward link and the link from a mobile station to a server is referred to as the reverse link.
In CDMA, network performance is defined by both the forward link and the reverse link. However, the performance of a CDMA network depends largely on system functions exercised by servers in the forward link because most of the information on timing and synchronization occurs on this link. Accordingly, the forward link behavior contributes significantly to overall network performance. Nevertheless, the amount of call traffic that can be supported, which determines the interference levels and ultimately the performance of both links, depends on the most limiting link, either the forward or the reverse link.
The forward link may be considered to be more limiting in a CDMA network scenario in which there are many servers, because a large number of servers correspondingly increases the interference experienced at the mobile station. Thus, the transmit power in the forward link may need to increase in order to overcome the interference. However, equipment settings may limit the system""s ability to compensate for the performance and thus the system at this location becomes forward limited. In an alternative scenario, the reverse link may be considered to be more limiting due to hardware constraints such as the particular type of voice coder, or vocoder, or limited transmit power used by the mobile stations.
The performance of the network depends on the most limiting link because the requirements of both links should desirably be satisfied in order for communication to be established. Therefore, the performances of the two links are tightly coupled. In an ideal network model and without considering any practical limitation, an analysis of both links should desirably be part of the same iterative procedure due to this tight coupling. Unfortunately, such an iterative process is extremely complex and impractical because of the excessive computation time that would be required.
Thus, what is needed is a system and method that accurately analyze network performance of both the forward and reverse links in a time and cost effective manner while maintaining overall system operation integrity.
Accordingly, it is an advantage of the present invention that a system and method is provided for analyzing the performance of a digital wireless communication network.
It is another advantage of the present invention that the system and method provide an accurate analysis of both forward link and reverse link performance.
It is another advantage of the present invention that a flexible architecture is provided that can be appropriately configured and interconnected to analyze the performance of the network in response to the more limiting of the forward and reverse links.
It is yet another advantage of the present invention that the system and method provide an accurate analysis of network performance while taking into consideration the practical limitations of computation complexity, execution time, and cost.
The above and other advantages of the present invention are carried out in one form by a computer-based method for analyzing a performance of a digital wireless network having sectors, the sectors being defined by locations. The method calls for identifying probable servers for the locations in the network and performing an initial reverse link assessment of the network. The method further calls for executing a forward link analysis in response to the performing operation and implementing a reverse link analysis in response to the executing operation.
The above and other advantages of the present invention are carried out in another form by a computing system for analyzing a performance of a digital wireless network having sectors, the sectors being defined by locations. The computing system includes a processor, a computer-readable storage medium, and executable code recorded on the computer-readable storage medium for instructing the processor to analyze the performance of the network. The executable code includes a probable server identification module for identifying probable servers for the locations in the network. A reverse link initial estimation module provides an initial reverse link assessment of the network, and a forward link initial estimation module provides an initial forward link assessment of the network. A forward link analysis module analyzes a forward link performance of the network, and a reverse link analysis module analyzes a reverse link performance of the network. The forward link analysis module analyzes the forward link performance in response to the initial reverse link assessment or the analyzed reverse link performance. Likewise, the reverse link analysis module analyzes the reverse link performance in response to the initial forward link assessment or the analyzed forward link performance.